The Gold P31 NVMe PCIe 3.0 x4 SSD in particular was the world's first consumer SSD with 128-layer NAND when it launched just over a month ago. Its $110 sale price will net users 3500 MB/s read and 3200 MB/s write speeds instead of the slower PCI x2 speeds commonly found in this price range.
https://www.notebookcheck.net/Cheap-SK-Hynix-Gold-P31-S31-NVMe-and-SATA-SSDs-are-now-even-cheaper-for-Amazon-Prime-Day.497512.0.html